COVID research updates: The immune trait that could allow viral reinfection
Nature wades through the literature on the new coronavirus — and summarizes key papers as they appear.
TEM of SARS-CoV-2 virus particles. Particles of SARS-CoV-2Credit: NIAID (CC BY 2.0)
2 October: The immune trait that could allow viral reinfection
Waning antibody levels or a poorly developed immune response to SARS-CoV-2 could put people at risk of reinfection, one case suggests.
In March, a care-home resident in their sixties developed severe pneumonia and tested positive for the new coronavirus. The individual spent more than one month in hospital before testing negative. In July, the individual tested positive again, with milder symptoms of coughing and shortness of breath.
What the immune response to the coronavirus says about the prospects for a vaccine Genomic analysis by Jason Goldman at the University of Washington, Seattle, and his colleagues (J. D. Goldman et al. Preprint at medRxiv https://doi.org/fbvj; 2020) showed that these were two separate infection events. The team also found that after the second infection, the individual produced only low levels of antibodies, and that these decreased over time. The person might have had a similar response to the first infection, which could explain why the individual was not protected against the second infection, the authors say.
The team also measured the individual s neutralizing antibodies, which protect cells against infection. The person had lower levels of these potent antibodies against the version of SARS-CoV-2 that caused the first infection than against the version that caused the second infection.
The researchers say that these measurements provide a useful benchmark for antibody levels that do not protect against reinfection. The research has not yet been peer reviewed.